Fire extinguisher charge



Sept. 20, 1932. R. c. mamas 1,878,795

' FIRE EXTINGUISHER canes Filed June 17 1929 m an Q 87 as i 4 o 8 I 86 a: 92.

INVENTOR BY W I ATTORNEYS.

Patented Sept. 20, 1932 i I futures STATES Fri c i.

ROSOOE C. IDDINGS, OF DAYTON, OHIO, ASSIGNOR TO THE FYR-FYTER COMPANY, OF

DAYTON, OHIO, A CORPORATION OF OHIO FIRE EXTINGUISHER CHARGE Application filed J 'un e 17, 1929. Serial No. 371,378.

This invention relates to fire extinguishers, and particularly to charges for fire extinguishers of the chemical reaction type.

One of the principal objects of this invention is to provide a charge for fire extinguishers of this type which will withstand extremely low temperatures without freezing, and which will react with high efficiency at suchextremely low temperatures.

Other objects and advantages of the invention will be apparent from the following description, the accompanying drawing and appended claims. a

In the drawing in which like characters of reference designate like parts throughout the several views thereof,

Fig. 1 is a central verticallsectional View through an extinguisher adapted to receive a Fig. 2 is a fragmentary vertical sectional view through a modified form of inner tube for the extinguisher of Fig. 1; and

Fig. 3 is a plan view looking upwardly upon the bottom of Fig. 2.

Of the chemical reaction type of extinguishers, that generally known as the soda and acidextinguisher is typical. One principal objection to an extinguisher of the soda and acid type, containing a solution such as a water solution of sodium bicarbonate, is that the solution will freeze at temperatures not much below the freezing point of water. Not

only does the bicarbonate solution freeze at low temperatures ordinarily encountered in temperate and cold climates, but furthermore the chemical reagents of the charge become so sluggish at low temperatures that the extinguisher becomes practically inoperative as far as effective fire extinguisher use is concerned.

In accordance with the present invention, a fire extinguisher charge is provided in which the various constituents or separate portions thereof will withstand temperatures as low as 40 C. without freezing, and the gas generating portions will react with high efliciency at such extremely low temperatures.

This is of peculiar importance because Underwriters Laboratories require this performance of an extinguisher in order to receive a preferred rating.

I have discovered that a gas forming ma terial, such as sodium bicarbonate, mixed with a metal, such as magnesium, will react with high efficiency with an acid liquid, such as hydrochloric acid, at extremely low temperatures of the order above mentioned. Better results are secured when the metal is finely divided, powdered magnesium being very satisfactory. The reaction of such a metal with an acid, such as hydrochloric acid, is highly exothermic, generating considerable heat and warming up the other materials of the charge to such a temperature that an efficient and effective reaction takes place between the acid and the carbonate bearing material. The entire reaction takes place quite rapidly so that a proper building up of gas pressure upon operation of the extinguisher is insured even at an extremely low temperature of the order of -40 C.

While I prefer to use powdered magnesium, other metals such as sodium or potassium will also function in this manner. However, the reaction is more diflicult to control with metals of the alkali group due to the violence of their reaction. Powdered magnesium on the other hand when used in the proper proportions gives a vigorous but readily controlled reaction with the acid liquid. Any suitable acid or acid salt which in solution will react with the metal may be used, but preferably a liquid which is non-freezing at such extremely low temperatures is used. Hydrochloric acid of a concentration of about 20% to 25% satisfies this requirement. Other commonly used acids, such as sulphuric acid of the proper concentration, may be used. Any suitable carbonate material, such as bicarbonate or a nor- .mal carbonate, is satisfactory.

ed to receive a three portion charge may be used. Referring to the drawing, there is shown therein a satisfactory extinguisher Y construction adapted to receive and operate upon the charge of this'invention. This extinguisher comprises a sheet metal outer container having a downwardly extending flange portion 11 forming a base upon which the extinguisher may sit in upright position. The lower end of the container is closed by a sheet metal bottom 12 which is attached to the inner wall of the shell in any suitable manner as by soldering. The top of the shell is provided with a centrally arranged opening whichreceives therein a cover casting 13 having a filling opening 14, and provided with an externally screw threaded portion 15 adapted to receive thereon a cover" 16. The cover 16 carries a suitable handle 17 which as shown is in the form of a ring to serve as abase upon which the extinguisher is adapted to rest when inverted. An annular washer 17 is positioned between'the cover. 16 and the upper end of the cover casting 13.

Adj acent theupper end ofthe extinguisher and passing through the wall of'the shell. is a discharge casting 20. This casting is provided with an enlarged shoulder 21 soldered to the shell towhich is secured a. screen 22 by an inturned lip 23; The outer end of the casting isprovided with a threaded nipple which receives the usual flexible hose carrying a discharge nozzle 26.

Supported within the outer container 10 is a normally closed sheet metal tube'30 provided at its upper end with external screw threads adapted to be received by internal screw threads carried by the cover 16. The tube is of slightly smaller diameter than the diameter of the filling opening 14 so that the tube 30 and mechanism carried thereby maybe inserted or withdrawn as a unit with the cover 16. Extending through an opening 34 in the bottom of the tubeBO. and soldered thereto is a supporting member or rod 35, to the upper end of which is attached a cup shaped member 37 carrying a cushioning seat. 38 of cork or other resilient material. Resting upon the seat 88 is the mouth of. an acid bottle 41, the neck of the bottle being closed by a stop 42. Restin upon the upper end of the bottle 41 is a second container 44 adapted to receive the'proper quantity of, mixedjcarbonate bearing salt. and finely divided metal. As is clearly evident from Fig.

1 of the drawing, a comparatively small container 44 suffices to hold the solid mlxed carbonate-metal portion of the charge. The usual quantity of carbonate in proportion to the quantity of acid may be employed as in the conventional charges of soda-acid extinguishers in. order to develop the customary expelling gas pressure. The amount of powdered metal in proportion to the carbonate may be varied over wide limits, it being only desirable that sufhcient metal be provided to generate heat by the exothermic reaction sufiicient to heat up the carbonate and acid portion of the charge when mixed from the low sub-freezing temperature to a temperature above the freezing point. of water, or: to areact-ive temperature as previously described. This may be easily determined from the known exothermicireaction of the powdered metal and acid, and the known specific heats of the carbonate and acid for the temperature rise desired. In the interests ofeconomy, it is desirable'that only'a small proportion of metal be used such as to give this required temperature rise, but the charge is fully operative over a wide range of proportions considerably in excess of this.- As an example of a charge in accordance with this invention for a 2% gallon extinguisher, the following is mentioned asgiving very satisfactory re.- sults 5.8 ounces dry sodium bicarbonate .4 ounces finely powdered magnesium 11.5 ounces hydrochloric acidjof about 22% strength The upper end of the container 44. isclosed.

by a stopper 45. When an acid, such as hydrochloric acid, is used, a hermetically sealed acid container is preferably used to prevent v fuming and corrosion, A closed container is also preferably provided for the carbonate and, powdered metal to insure against undesired reaction shouldthe acid container be cracked or leakage occur. 5

Centrally arranged on the cover 16 isfan. opening through which extends a slidable plunger 51. A. stuffingbox is formed about the plunger to prevent leakage. This comprises an upstanding threaded flange 52 carried by the cover receiving a screw cap 53 to compress within the packing gland suitable packing 54. The lower end of the plunger rod 51 which extends through the cover 16 to the interior ofthe extinguisher is provided with an interior bore 55 adapted to loosely receive therein an upper extension 56 of smaller diameter of a second plunger rod 57. This plunger rod 57 slijdably extendsithrough an opening 58 in the stopper 45, the lower end of the plunger rod being pointed as at 59 and terminating short of the bottom of the V container 44.; The inner end of the plunger rod51 is preferably provided with exterior. screw threads 60 adapted to receive thereon a nut 61 to prevent the plunger rod 51 fromb radial ing withdrawn from the extinguisher. The rod 51 in its normal position extends above handle 17 and is provided with an operating button 62.

T0. permit the gaseous pressure to be communicated from within the tube to the spaced within the outer container 10, a valve controlled passage 63 is formed within the supporting rod 35. As shown, the upper end of the passage 63 opens by a plurality of ports 64 into the space within the tube 30 adjacent the bottom thereof, and the lower I end of the passage 63 opens by a plurality of radial ports 65 into the space within the outer container 10 adjacent the lower end thereof. The'passage 63 is provided with a yalvejseat 66 which normally receives in seallng engagement a spring pressed valve 67. A

spring 68 bears respectively against the bottom of the rod 35 and a collar 69 on the valve stem 70 which is slidably mounted in the bottom of the rod 35.

This construction prevents the fire extinguishing llquid within the outer container from passing into the tube 30. When the extinguisher is inverted, the outlet ports 65 valve 67,

of the passage 63 are then disposed above the liquid level within the outer container. The gas pressure produced within the tube 30 by reaction of the generating materials overcomes the tension of the spring 68 to open the permitting the gas to pass through 1 the passage 63 into the space within the outer uid. I

container to expel the fire extinguishing liq- In' operation, the extinguisher is inverted and bumped down upon the floor or other v convenient surface, driving the plunger rods 51 and 57 inwardly. The bottom 7 5 of the container 44, and the inverted bottom 7 6 of the container 41 are formed of a thin frangible material, such as glass, whereby the pointed end59 of the plunger breaks the two frangible containers permitting the acid with the evolution of CO gas results. This gas passes through the valve controlled passage 63 into the upper end of the now inverted container 10 to produce an expelling pressure therein.

i In Flgs. 2 and 3 is shown a somewhat mod-1- fied form ofinner tube and valve controlled pressure discharge. This comprises a sheet metal tube 30 which may be suspended from the cover as shown in Fig. 1. The tube is provided with a cast metal bottom having a threaded opening 81 adapted to receive an upstanding supporting rod 35 which sup ports the cup shaped acid container 37 The casting 80 is also provided with an opening 82 receiving therein a hollow tube 83,the lower end of which is formed with a valve seat 84, with which cooperates a valve 85 carried by one arm of alever 86. Rigidly fastened below the casting 80 is a casting 87 which is bifurcated to provide two spaced extending arms indicated at88 and 89. The casting 87 provides a lower support as indicated at 90 for the tube 83. A pin 91 is mounted between thearms 88 and 89, and the lever 86 is pivotally mounted upon this pin. The other arm of the lever 86-carries a lead weight 92, which in the upright position of the extinguisher urges the valve 85 into sealing engagement with the valve seat 84 to prevent the ingress of liquid into the tube 30. The ends of the arms 88 and 89 are curved downwardly as indicated at 93 to properly guide the rocking movement of the lever 86.

In operation, when the extinguisher is inverted, the weight 92 rocks the leverby the force of gravity about the pivot pin 9l to re move the valve 85 from its seat 84', thereby permitting the gas pressure generated within the tube 32 to passfreely into the space within the outer container.

a While the forms of invention herein described constitute preferred embodiments thereof, it is to be understood that the invention is not to be limited to these precise forms, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. In a fire extinguisher charge, a normally separated gas generating portion comprising a gas forming material and a metal.

2. In a fire extinguisher charge, a normal- 1y separated gas generating portion comprising a carbonate bearing material mixed with a finely divided metal.

3. In a fire extinguisher charge, a normally separated gas generating portion comprising a carbonate bearing material mixed with powdered magnesium.

4. A fire extinguisher charge comprising as normally separated portions, an acid liquid,- and a metal adapted to react exothermically therewith.

5. A fire extinguisher charge comprising as normally separated gas generating portions,

an acid liquid, and a gas forming material adapted to react at normal temperatures with said acid liquid, mixed with a metal adapted to react exothermically with the acid liquid to generate heat to promote the reaction of the said gas forming material with the acid liquid at temperatures below said nor-. mal temperatures.

6. A fire extinguisher charge comprising an acid, a carbonate bearing material, and a to the interior wall of the tube 30 iii.

finely divided metal adapted to react exothermically with the acid.

7; A fire extinguisher charge as normally separated portions, an acid, and a dry carbonate bearing material mixed with powdered magnesium.

8. A fire extinguisher charge comprising as normally separated portions, hydrochloric acid, and a dry carbonate bearing material mixed with powdered magesium.

9. A fire extinguisher charge comprising as normally separated portions, a fire extinguishing'liquid which is non-freezing at low temperatures, an acid liquid which is also comprising non-freezing at low temperatures,and agas generating material'mixed with a finely divided metal.

10. A fire extinguisher charge comprising as normally separated portions, a fire extinguishing liquid which is non-freezing at low temperatures, an acid which is also nonfreezing at such low carbonate hearing material mixed with powdered magnesium. 7

In testimony whereof I hereto afix my signature.

ROSGOE G. IDDINGS.

temperatures, and a dry 

